Access to buildings such as office buildings and apartment buildings is often restricted and the entrance doors are locked so that visitors cannot enter the building without having received permission or authorisation to do so from a resident of the building. In order to request access the visitor will usually ring the door bell of the resident he wishes to visit. For this purpose fixtures, such as nameplates are located next to an entrance of the building along with associated bell buttons, allowing the visitor to determine who is a resident of the building and to alert the resident that there is a visitor waiting at the entrance. The alerted resident will then typically establish contact with the visitor by means of an intercom system installed within the building. Once the resident has established the identity of the visitor, he may provide access into the building by unlocking the entrance door. Usually, the resident is able to remotely unlock the entrance door via the intercom system. A disadvantage of the presently required fixtures (e.g. nameplates, bell buttons and intercom system) is the high cost involved with their installation and maintenance. Moreover, they usually require dedicated wiring within the building and impose certain restrictions on the layout of the building (since considerable space is needed at the entrance especially for large buildings with many residents). Furthermore, nameplates have to be maintained up-to-date when residents change. Hence, there is a need for an improved means for providing visitors controlled access into buildings.